Grip pulley

ABSTRACT

A pulley for a flexible drive belt comprising a circular web having a plurality of fins extending outwardly therefrom arranged in circumferentially spaced sets diverging outwardly from each other to form a V-groove therebetween and each being connected to said web by an integral reinforcing member partially cut from the material of the web and the fin.

United States Patent [191 Kahmann [451 Oct. 9, 1973 GRIP PULLEY [76] Inventor: Manfred Kahmann, 1520 V2 Birchwood, Chicago, Ill. 60626 [22] Filed: Dec. 20, 1971 [21] Appl. No.: 209,925

[52] US. Cl. 74/230.3, 74/2300] [51] Int. Cl. Fl6h 55/36 [58] Field of Search 74/2303, 230.8,

[56] References Cited UNITED STATES PATENTS 1,668,778 5/1928 Menningen 74/2305 2,074,199 3/1937 Arnold 74/230.8

3,320,823 5/1967 Kjellstron 74/2305 429,408 6/1890 Avery 113/116 D 2,432,185 12/1947 Watson 113/116 D 2,933,935 4/1960 Sterkel 74/230.5

Primary ExaminerCharles J. Myhre Assistant Examiner-R. H. Lazarus Attorney-Richard W. Carpenter [57] ABSTRACT A pulley for a flexible drive belt comprising a circular web having a plurality of fins extending outwardly therefrom arranged in circumferentially spaced sets diverging outwardly from each other to form a V- groove therebetween and each being connected to said web by an integral reinforcing member partially cut from the material of the web and the fin.

7 Claims, 6 Drawing Figures GRIP PULLEY This invention relates to pulleys and more particularly to non-slip pulley for gripping a flexible drive belt such as a conventional V-belt.

The basic concept of providing pulleys which include central webs with alternately diverging fins is not new per se. However it is an object of this invention to provide an improved arrangement of this type which overcomes certain of the common problems associated with known prior art arrangements such as those of the type illustrated in United States Letters Patent Nos. 2,074,199; 3,320,823; and 3,394,606.

The problem most common to arrangements which rely on a central web with alternately diverging fins to provide an undulating motion of the drive belt to prevent slippage is that the fins tend to break off the web or to be deformed or deflected out of their proper positions under high speeds and/or heavy loads. While it is possible to form a pulley of this type from a heavy casting, the cost of such a structure is obviously relatively high.

It is therefore a primary object of this invention to provide, in a pulley of the type described, a device which is formed from sheet material so as to be relatively lightweight and therefor relatively inexpensive to produce, and which, at the same time, is relatively strong and rigid so as to be capable of efficient performance at high speeds and/or heavy loads without easily being deformed or deflected.

A more specific object of the invention is the provision of a pulley having a central web and a plurality of alternately spaced sets of outwardly diverging fins which form a V-groove therebetween and which are also each connected to the web by an integrally formed reinforcing member cut away from the material of the web and related fin and which has an intermediate portion spaced therefrom.

These and other objects of the invention will be apparent from an examination of the following description and drawing, wherein:

FIG. 1 is a side elevation of a pulley embodying features of the invention;

FIG. 2 is an end elevation of the structure illustrated in FIG. 1;

FIG. 3 is a section taken on line 3-3 of FIG. 1;

FIG. 4 is a view similar to FIG. 3, but illustrating a modified form of the invention; and

FIGS. 5 and 6 are fragmentary sections taken on lines 5-5 and 66, respectively of FIG. 4.

It will be understood that, for purposes of clarity, certain elements have been intentionally omitted from certain views where they are believed to be illustrated to better advantage in other views.

Referring now to the drawing for a better understanding of the invention, and particularly to FIGS. 1 and 3, it will be seen that there is illustrated a pulley, indicated generally at P, which embodies features of the invention and which is mounted on a shaft S and around which is carried a conventional V-type, flexible drive belt B.

As best seen in FIG. 1, pulley P includes a central hub.

10, mounted on a shaft S.

Turning to FIG. 3, it will be seen that pulley P includes a relatively flat, circular plate or web 12 which may be secured to hub in any desired manner such as by welds 14.

Formed integrally with and extending radially outward from the outer periphery of web 12 are a plurality of fins 16 which are arranged in circumferentially spaced sets, each diverging axially outward from the other and from the plane of web 12 to form a generally annular V-groove having interrupted side walls, with each side wall having openings opposite the solid portions of the opposite side wall.

As best seen in FIGS. 2 and 3, each of the fins 16 is somewhat V-shaped in corss-section and comprises a pair of relatively flat sections 18 which converge axially inward to present a radially extending ridge 19 facing the V-groove.

The ridge 19 of each fin 16 provides the primary line .of contact between the fin and belt B, so that, as best seen in FIG. 2, the belt travels around the pulley in an undulating path. This assures a more positive contact between the belt and pulley and minimizes slippage therebetween.

The primary novelty in the present invention resides in the structural arrangement of the struts 20 wich connect the web 12 to the fins 16. The struts not only serve to reinforce structurally the fins, but they also assist in cooling the fins by diverting or trapping the flow of air around the area where the fins are joined to the web.

As best seen in FIGS. 1 and 2, struts 20 have opposed side edges 22 cut from the material of the web and fins and each strut comprises a relatively narrow elongated strip of material joined at its inner end to the web and joined at its outer end to a related fin. Thus, each fin is in the shape of a bridge with a center portion bowed axially outward from the outer surfaces of the web and related fin to present a space 24 therebetween. As the pulley rotates air passes through the openings 24 of each strut and is deflected against surfaces of the web and related fin to assist in cooling the fins.

By shear forming the struts in the manner of the present invention, they can be much lighter in weight than heavy solid or molded reinforcing members of known prior art devices and can still perform with equal or greater efficiency at less cost.

FIGS. 4, 5, and 6 illustrate a slightly modified form of the invention. All of the portions of the structure which are similar to the previous embodiment are indicated by corresponding numerals.

The primary difference in this embodiment resides in the shape of the fins which have only one side edge 122 cut away from the material of the web and related fin. Fins 120 each have a raised or offset center portion which is curved, as seen in FIG. 6 to define a cup-like pocket 124 which serves as a cooling vane to deflect the flow of air over the adjacent surfaces of the web and related fin.

As best seen in FIG. 4, it will be seen that in this embodiment of the invention the trailing tips, 126 of each fin is bent outwardly a slight amount at provide another means of deflecting air around the fins to assist in cooling the outer periphery of the pulley.

I claim:

1. In a pulley for a flexible V-type drive belt, the combination of:

a. a single, unitary, generally flat, circular, central web;

b. a plurality of fins formed integrally with and extending radially outward from the outer periphery of said web;

c. said fins being arranged in alternately circumferentially spaced sets, each diverging axially outward from the other and from the plane of said web in opposite directions to form a generally annular V- groove having interrupted side walls, with each side wall having openings opposite the solid portions of the opposite side wall;

d. integrally formed reinforcing members connecting said fins to said web;

e. each of said members comprising a relatively narrow elongated strip having:

i. an inner end portion connected to said web;

ii. an outer end portion connected to a related fin;

iii. at least one side edge free from attachment to the material of said web and said related fin;

iv. an intermediate portion spaced axially outward from the outer surfaces of said web and said related fin.

2. A pulley according to claim 1, wherein said strip has a pair of opposite side edges free from attachment to the material of said web and said related fin to form a bridge therebetween which is spaced therefrom throughout substantially its entire length.

3. A pulley according to claim 1, wherein said strip has only one side edge free from attachment to the material of said web and said related fin and another side edge joined to the material of said web and said related fin to form therewith a pocket open on one side.

4. A pulley according to claim 1, wherein each of said fins is slightly V-shaped in transverse cross section and comprises a pair of generally flat sections which converge axially inwardly to present a radially extending central ridge facing said V-groove.

5. A pulley according to claim 1, wherein each of said reinforcing members forms with related portions of said web and said related fin a pocket open toward the leading edge of said related fin and closed toward the trailing edge of said related fin.

6. A pulley according to claim 1, wherein each of said fins presents a radially extending central ridge facing into said V-groove.

7. A pulley according to claim 6, wherein each of said reinforcing members is joined to a central portion of its related fin in alignment with the central ridge of said fin. 

1. In a pulley for a flexible V-type drive belt, the combination of: a. a single, unitary, generally flat, circular, central web; b. a plurality of fins formed integrally with and extending radially outward from the outer periphery of said web; c. said fins being arranged in alternately circumferentially spaced sets, each diverging axially outward from the other and from the plane of said web in opposite directions to form a generally annular V-groove having interrupted side walls, with each side wall having openings opposite the solid portions of the opposite side wall; d. integrally formed reinforcing members connecting said fins to said web; e. each of said members comprising a relatively narrow elongated strip having: i. an inner end portion connected to said web; ii. an outer end portion connected to a related fin; iii. at least one side edge free from attachment to the material of said web and said related fin; iv. an intermediate portion spaced axially outward from the outer surfaces of said web and said related fin.
 2. A pulley according to claim 1, wherein said strip has a pair of opposite side edges free from attachment to the material of said web and said related fin to form a bridge therebetween which is spaced therefrom throughout substantially its entire length.
 3. A pulley according to claim 1, wherein said strip has only one side edge free from attachment to the material of said web and said related fin and another side edge joined to the material of said web and said related fin to form therewith a pocket open on one side.
 4. A pulley according to claim 1, wherein each of said fins is slightly V-shaped in transverse cross section and comprises a pair of generally flat sections which converge axially inwardly to present a radially extending central ridge facing said V-groove.
 5. A pulley according to claim 1, wherein each of said reinforcing members forms with related portions of said web and said related fin a pocket open toward the leading edge of said related fin and closed toward the trailing edge of said related fin.
 6. A pulley according to claim 1, wherein each of said fins presents a radially extending central ridge facing into said V-groove.
 7. A pulley according to claim 6, wherein each of said reinforcing members is joined to a central portion of its related fin in alignment with the central ridge of said fin. 